Grand National contenders Tidal Bay and Rocky Creek delighted their trainer, Paul Nicholls, in an eight-horse racecourse gallop at Wincanton on Monday morning. Tidal Bay, in particular, had Nicholls brimming with enthusiasm as he watched an exercise intended to bring the pair to peak condition for the race at Aintree on 5 April.

"Look at him, he's still fresh," the plainly impressed trainer said as he drove alongside Tidal Bay, almost at the end of the two-mile, half-speed workout. The two National entrants started 10 lengths behind another pair of their stablemates but finished close behind, travelling strongly, with their Aintree jockeys aboard, Sam Twiston-Davies on Tidal Bay and Noel Fehily on Rocky Creek.

Twiston-Davies reported that after passing the winning post in the gallop it took him 100 yards longer to steady Tidal Bay to a walk than the other riders had needed for their mounts. "It's amazing, a horse of his age," Nicholls said of the 13-year-old.

"He's just got so much class, it's quite something he is. I just wish he was still eight years old but he seems better now than ever. To work with those young horses like that …

"Tidal hasn't run for a while, he loved doing that and the day out will have done him the world of good."

"He was brilliant," the jockey reported. "We did two miles and he was still pulling after a mile and a half, so I couldn't be more happy with him. The way he walks in here, you couldn't believe how old he is," Twiston-Davies said of the horse's swaggering demeanour and ostentatious wellbeing. "He feels in great form."

Nicholls was also pleased with Rocky Creek, who had to miss the recent Gold Cup because he was suffering from ringworm, a cosmetic problem but an infectious one that meant it would be irresponsible to take him to Cheltenham. The trainer appeared a touch rueful about that, since the race turned out to be short on quality.

"He could have run really well in that," Nicholls said. "But, anyway, we're in the National now and looking forward to it." For various reasons, he feels he has never had Rocky Creek as fit as he would have liked this season. "He's got a little bit to prove because he was second last time [at Cheltenham in January] but I think he is capable of running really, really well."

The other six horses in the gallop also have races at Aintree next week as their targets. The grey Unioniste appeared bursting with vigour, despite a disappointing effort when last seen two months ago, and the trainer may run him in the Betfair Bowl or in a staying handicap chase.

Rolling Aces, who worked alongside him, is being aimed at the Melling Chase, while Cedre Bleu is in the Topham and Rebel Du Maquis in the Fox Hunters. Vicenzo Mio will run in the juvenile hurdle and worked with another promising youngster, Alibi De Sivola, reckoned to have improved enormously since his racecourse debut last month.

"I'm pleased with them all," Nicholls said. "The lads have said they did a serious piece of work, they all went really nicely."

They form only part of a strong team to be sent from Nicholls's yard, about nine miles from here at Ditcheat, to Aintree as he attempts to wrest back his champion trainer's title from Nicky Henderson. "We're about £480,000 in front but the National can wipe that out in one go," he said.

"Other than that, it's dead handy. I never thought we'd be in this position. There's a month with a lot of good racing and we've still got to keep on our toes. It's an exciting position to be in but there's some really exciting racing, so we keep going."

Looking beyond that, Nicholls said it would be a mistake to assume that the National will be Tidal Bay's final outing before retirement. "I could see him being in training for a couple more years yet because he's not the easiest horse in the world to retire, for the simple reason that he's almost dangerous in a box. You couldn't just give him to anybody.

"We've just said, if he's fit and healthy and enjoying himself, we'll be very selective with what we do with him. If he went and won the National that might well be a case of having to retire him. But if he didn't and he's in good shape, we can mix and match him over hurdles and fences. But those decisions are for the future. At the moment, we just see how he is."